Soluble heterometallic coordination polymers based on a bis-terpyridine-functionalized dioxocyclam ligand.

Soluble homo- and heterometallic coordination polymers containing transition metal cations (Cu(2+), Fe(2+), Co(2+), and Ni(2+) ions) were prepared in a two-step procedure using a polytopic bis(terpyridine)dioxocyclam ligand 1H(2) (dioxocyclam = 1,4,8,11-tetraazacyclotetradecane-5,7-dione). These supramolecular systems incorporate two different metal complexes, the metal cations being located both between two terpyridine units and in the macrocyclic framework. The characterization of these soluble architectures was investigated by cyclic voltammetry, mass spectrometry, viscosimetry, and UV-vis absorption and electron paramagnetic resonance (EPR) spectroscopies. Our results clearly indicate the formation of well-organized heterometallic polymers in which two different metal ions alternate in the self-assembled structure. These investigations furthermore brought to light an original acid-controlled disassembling process of the homometallic copper(II) polymer into dinuclear complexes.